Battery with multiple jelly rolls in a single pouch

ABSTRACT

The disclosed embodiments provide a battery cell which includes a set of jelly rolls enclosed in a pouch. Each jelly roll includes layers which are wound together, including a cathode with an active coating, a separator, and an anode with an active coating. The battery cell also includes a first set of conductive tabs and a second set of conductive tabs. Each of the first set of conductive tabs is coupled to the cathode of one of the jelly rolls, and each of the second set of conductive tabs is coupled to the anode of one of the jelly rolls. At least one of the first set and one of the second set of conductive tabs extend through seals in the pouch to provide terminals for the battery cell.

RELATED APPLICATION

This application is a continuation of, and hereby claims priority under35 U.S.C. § 120 to, pending U.S. patent application Ser. No. 12/694,144,entitled, “Battery with Multiple Jelly Rolls In a Single Pouch,” byinventors Ramesh C. Bhardwaj, Taisup Hwang and Richard M. Mank, filed on26 Jan. 2010.

BACKGROUND

Field

The present embodiments relate to batteries for portable electronicdevices. More specifically, the present embodiments relate to batterycells with multiple jelly rolls in a single pouch.

Related Art

Rechargeable batteries are presently used to provide power to a widevariety of portable electronic devices, including laptop computers, cellphones, PDAs, digital music players and cordless power tools. The mostcommonly used type of rechargeable battery is a lithium battery, whichcan include a lithium-ion or a lithium-polymer battery.

Lithium-polymer batteries often include cells that are packaged inflexible pouches. Such pouches are typically lightweight and inexpensiveto manufacture. Moreover, pouches may be tailored to various celldimensions, allowing lithium-polymer batteries to be used inspace-constrained portable electronic devices such as mobile phones,laptop computers, and/or digital cameras. For example, a lithium-polymerbattery cell may achieve a packaging efficiency of 90-95% by enclosing ajelly roll and electrolyte in a foil pouch. Multiple pouches may then beplaced side-by-side within a portable electronic device and connected inseries and/or in parallel to form a battery for the portable electronicdevice.

Hence, the use of portable electronic devices may be facilitated byimprovements related to the packaging efficiency, capacity, form factor,cost, and/or manufacturing of lithium-polymer battery cells.

SUMMARY

The disclosed embodiments provide a battery cell which includes a set ofjelly rolls enclosed in a pouch. Each jelly roll includes layers whichare wound together, including a cathode with an active coating, aseparator, and an anode with an active coating. The battery cell alsoincludes a first set of conductive tabs and a second set of conductivetabs. Each of the first set of conductive tabs is coupled to the cathodeof one of the jelly rolls, and each of the second set of conductive tabsis coupled to the anode of one of the jelly rolls. At least one of thefirst set and one of the second set of conductive tabs extend throughseals in the pouch to provide terminals for the battery cell.

In some embodiments, the jelly rolls are electrically connected withinthe pouch or outside the pouch using the first and second sets ofconductive tabs.

In some embodiments, the jelly rolls are electrically connected in aseries configuration, in a parallel configuration, or in a series andparallel configuration.

In some embodiments, the jelly rolls are internally separated within thepouch if the jelly rolls are electrically connected in the seriesconfiguration.

In some embodiments, the jelly rolls are of different thicknesses.

In some embodiments, the jelly rolls are sealed in the pouch based on anasymmetric battery design.

In some embodiments, sealing the jelly rolls in the pouch involves atleast one of gluing the jelly rolls to the inside of the pouch andplacing the jelly rolls within a set of frames inside the pouch.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a battery cell in accordance with an embodiment.

FIG. 2 shows a battery cell in accordance with an embodiment.

FIG. 3 shows a battery cell in accordance with an embodiment.

FIG. 4 shows a battery cell in accordance with an embodiment.

FIG. 5 shows a battery cell in accordance with an embodiment.

FIG. 6 shows a flowchart illustrating the process of manufacturing abattery cell in accordance with an embodiment.

FIG. 7 shows a portable electronic device in accordance with anembodiment.

In the figures, like reference numerals refer to the same figureelements.

DETAILED DESCRIPTION

The following description is presented to enable any person skilled inthe art to make and use the embodiments, and is provided in the contextof a particular application and its requirements. Various modificationsto the disclosed embodiments will be readily apparent to those skilledin the art, and the general principles defined herein may be applied toother embodiments and applications without departing from the spirit andscope of the present disclosure. Thus, the present invention is notlimited to the embodiments shown, but is to be accorded the widest scopeconsistent with the principles and features disclosed herein.

The data structures and code described in this detailed description aretypically stored on a computer-readable storage medium, which may be anydevice or medium that can store code and/or data for use by a computersystem. The computer-readable storage medium includes, but is notlimited to, volatile memory, non-volatile memory, magnetic and opticalstorage devices such as disk drives, magnetic tape, CDs (compact discs),DVDs (digital versatile discs or digital video discs), or other mediacapable of storing code and/or data now known or later developed.

The methods and processes described in the detailed description sectioncan be embodied as code and/or data, which can be stored in acomputer-readable storage medium as described above. When a computersystem reads and executes the code and/or data stored on thecomputer-readable storage medium, the computer system performs themethods and processes embodied as data structures and code and storedwithin the computer-readable storage medium.

Furthermore, methods and processes described herein can be included inhardware modules or apparatus. These modules or apparatus may include,but are not limited to, an application-specific integrated circuit(ASIC) chip, a field-programmable gate array (FPGA), a dedicated orshared processor that executes a particular software module or a pieceof code at a particular time, and/or other programmable-logic devicesnow known or later developed. When the hardware modules or apparatus areactivated, they perform the methods and processes included within them.

The disclosed embodiments provide a battery cell containing a set ofjelly rolls enclosed in a pouch. Each jelly roll includes layers whichare wound together, including a cathode with an active coating, aseparator, and an anode with an active coating. The battery cell alsoincludes a first conductive tab coupled to the cathode of one or more ofthe jelly rolls and a second conductive tab coupled to the anode of oneor more of the jelly rolls. The first and second conductive tabs extendthrough seals in the pouch to provide terminals for the battery cell.The first and second conductive tabs may also be used to electricallyconnect the jelly rolls within the pouch or outside the pouch, in seriesand/or in parallel.

The jelly rolls may be of different thicknesses and sealed in the pouchbased on an asymmetric battery design. As a result, the battery cell maybe designed to accommodate the space constraints of a portableelectronic device such as a laptop computer, mobile phone, personaldigital assistant (PDA), digital camera, and/or portable media player.For example, jelly rolls of various thicknesses may be stacked, placedside-by-side, and/or placed top-to-bottom within the pouch to fit thebattery cell behind the display of a laptop computer. The use ofmultiple jelly rolls in a single pouch may additionally provideadvantages related to battery packaging efficiency, capacity,manufacturing, and/or cost.

FIG. 1 shows a battery cell 100 in accordance with an embodiment.Battery cell 100 includes a set of jelly rolls 101-103 and a set ofconductive tabs 104-109. Each jelly roll 101-103 includes a number oflayers which are wound together, including a cathode with an activecoating, a separator, and an anode with an active coating. Jelly rollsare well known in the art and will not be described further.

In one or more embodiments, jelly rolls 101-103 are enclosed in aflexible pouch, which is formed by folding a flexible sheet along a foldline 112. For example, the flexible sheet can be comprised of aluminumwith a polymer film, such as polypropylene. After the flexible sheet isfolded, the flexible sheet can be sealed, for example by applying heatalong side seal 111 and along a terrace seal 110. Jelly rolls 101-103may be sealed within the pouch by gluing jelly rolls 101-103 to theinside of the pouch and/or placing jelly rolls 101-103 within a set offrames inside the pouch.

Furthermore, jelly rolls 101-103 may be coupled to conductive tabs104-109 and to one another through conductive tabs 104-109. Inparticular, jelly roll 101 is coupled to conductive tabs 104-105, jellyroll 102 is coupled to conductive tabs 106-107, and jelly roll 103 iscoupled to conductive tabs 108-109. Conductive tab 104 extends throughterrace seal 110 to provide a positive terminal for battery cell 100,and conductive tab 109 extends through terrace seal 110 to provide anegative terminal for battery cell 100.

In one or more embodiments, conductive tabs 104, 106, and 108 arerespectively coupled to the cathodes of jelly rolls 101, 102, and 103,while conductive tabs 105, 107, and 109 are respectively coupled to theanodes of jelly rolls 101, 102, and 103. Jelly rolls 101-103 may then beelectrically connected in a parallel configuration by couplingconductive tabs 106 and 108 to conductive tab 104 and by couplingconductive tabs 105 and 107 to conductive tab 109 within the pouch. Asdiscussed below with respect to FIG. 2, conductive tabs 104-109 may alsobe used to connect jelly rolls 101-103 within or outside the pouch in aseries configuration or a series-and-parallel configuration.

A battery pack may further be formed by coupling together a number ofbattery cells (e.g., battery cell 100) in a series, parallel, orseries-and-parallel configuration. As a result, complex batteryconfigurations may be achieved by electrically connecting jelly rollswithin each battery cell, as well as battery cells within the batterypack, in various series and/or parallel configurations. The coupledcells may be enclosed in a hard case to complete the battery pack, orthe coupled cells may be embedded within the enclosure of a portableelectronic device, such as a laptop computer, mobile phone, personaldigital assistant (PDA), digital camera, and/or portable media player.

Because battery cell 100 contains multiple jelly rolls 101-103 enclosedwithin a single pouch, battery cell 100 may provide increased packagingefficiency and/or capacity over battery cells that contain only onejelly roll per pouch. For example, if side seal 111 is 4 mm wide,battery cell 100 may provide the same capacity as three battery cellscontaining one jelly roll each while reducing the width required for thejelly rolls by 16 mm. Conversely, battery cell 100 may provide threetimes more capacity than a battery cell formed by enclosing only onejelly roll in a pouch.

FIG. 2 shows a battery cell 200 in accordance with an embodiment. Aswith battery cell 100 of FIG. 1, battery cell 200 includes a set ofjelly rolls 201-203 enclosed within a pouch and a set of conductive tabs204-209 coupled to jelly rolls 201-203. For example, conductive tabs204, 206, and 208 may be respectively coupled to the cathodes of jellyrolls 201, 202, and 203, while conductive tabs 205, 207, and 209 may berespectively coupled to the anodes of jelly rolls 201, 202, and 203.However, all conductive tabs 204-209 extend through seals in the pouch,allowing jelly rolls 201-203 to be electrically connected outside thepouch.

In particular, jelly rolls 201-203 may be connected in a series,parallel, or series-and-parallel configuration using conductive tabs204-209. For example, jelly rolls 201-203 may be connected in a parallelconfiguration by coupling conductive tabs 204, 206, and 208 to oneanother and by coupling conductive tabs 205, 207, and 209 to oneanother. On the other hand, jelly rolls 201-203 may be connected in aseries configuration by coupling conductive tab 205 with conductive tab206, coupling conductive tab 207 with conductive tab 208, and usingconductive tabs 204 and 209 as the positive and negative terminals ofthe battery cell, respectively.

As shown in FIG. 2, the pouch includes two internal separations 210-211between jelly rolls 201-203. Internal separations 210-211 may be used tocreate compartments that physically separate jelly rolls 201-203 fromone another. Such physical separation may allow series connectionsbetween jelly rolls 201-203 to produce voltage increases in the batterycell. Internal separations 210-211 may be created by forming indentsand/or ridges in a flexible sheet used to create the pouch. As the sheetis folded and sealed, spot welding may be used to connect the indentsand/or ridges. The compartments created using the indents and/or ridgesmay then be separately filled with one or more jelly rolls andelectrolyte.

FIG. 3 shows a battery cell 300 in accordance with an embodiment. Aswith FIGS. 1-2, battery cell 300 includes a set of jelly rolls 301-303enclosed within a pouch, as well as a set of conductive tabs 304-309coupled to jelly rolls 301-303 and to one another. In particular,conductive tabs 304, 306, and 308 are respectively connected to thecathodes of jelly rolls 301, 302, and 303 and to one another, andconductive tabs 305, 307, and 309 are respectively connected to theanodes of jelly rolls 301, 302, and 303 and to one another. Conductivetab 304 extends through the seal of the pouch to provide a positiveterminal for battery cell 300, and conductive tab 309 extends throughthe seal of the pouch to provide a negative terminal for battery cell300. Alternatively, as with FIG. 2, conductive tabs 304-309 may allextend through the seal of the pouch to enable electrical connectionsbetween jelly rolls 301-303 outside the pouch.

In addition, battery cell 300 contains jelly rolls 301-303 of differentthicknesses and/or sizes. As shown in FIG. 3, jelly roll 301 isthinnest, jelly roll 303 is of medium thickness, and jelly roll 302 isthe thickest. Furthermore, jelly rolls 301-303 may be placed in thepouch based on an asymmetric battery design that allows battery cell 300to fill up the free space within a portable electronic device. Forexample, jelly rolls 301-303 and/or other jelly rolls may be placedside-by-side, placed top-to-bottom, and/or stacked within the pouch tofit battery cell 300 around other components inside a mobile phone,laptop computer, portable media player, digital camera, and/or PDA.

FIG. 4 shows a battery cell in accordance with an embodiment. Inparticular, FIG. 4 shows a side view of battery cell 300 of FIG. 3, withjelly rolls 401-403 corresponding to jelly rolls 301-303. Because jellyroll 402 is thicker than jelly rolls 401 and 403, jelly roll 402 takesup more space in at least two dimensions within the pouch than jellyrolls 401 and 403. Jelly roll 403 takes up the second largest amount ofspace in at least two dimensions, and jelly roll 401 takes up the leastamount of space in at least two dimensions. As discussed below withrespect to FIG. 5, jelly rolls within battery cells may also vary inlength, thus allowing for asymmetric battery designs that utilize spacewithin portable electronic devices in all three dimensions.

FIG. 5 shows a battery cell in accordance with an embodiment. Thebattery cell includes four jelly rolls 501-504 of different thicknessesand lengths. Jelly rolls 501-503 are placed side-by-side within thepouch, and jelly roll 504 is placed top-to-bottom with jelly rolls501-502. The battery cell may also include jelly rolls that are stackedon top of each other. For example, additional jelly rolls may be stackedon top of jelly rolls 501-504 to increase the thickness of the pouch inone or more dimensions.

The battery cell additionally includes pairs of conductive tabs 505-508coupled to jelly rolls 501-504 and extended through seals in the pouch.Within each pair of conductive tabs, one conductive tab is coupled tothe cathode of a jelly roll, and the other conductive tab is coupled tothe anode of the same jelly roll. Jelly rolls 501-504 may then beelectrically connected in series and/or in parallel by couplingconductive tabs 505-508 in various configurations outside the pouch. Asdescribed above, jelly rolls 501-504 may include internal separationswithin the pouch if series connections between jelly rolls 501-504 areto be made.

As a result, the use and placement of multiple jelly rolls of differentlengths and thicknesses within a pouch may allow the creation of acustom battery cell that maximizes the use of free space within aportable electronic device and provides greater capacity, packagingefficiency, and/or voltage than battery cells that contain only onejelly roll per pouch. For example, multiple thin jelly rolls may beplaced side-by-side and/or top-to-bottom within a pouch to create abattery cell that fits behind the display of a laptop computer andprovides power to the laptop computer. Along the same lines, jelly rollsof various thicknesses and lengths may be sealed in a pouch to create anasymmetric battery cell that fits around other components (e.g.,processors, printed circuit boards (PCBs), memory, storage, etc.) insidethe enclosure of a mobile phone.

FIG. 6 shows a flowchart illustrating the process of manufacturing abattery cell in accordance with an embodiment. In one or moreembodiments, one or more of the steps may be omitted, repeated, and/orperformed in a different order. Accordingly, the specific arrangement ofsteps shown in FIG. 6 should not be construed as limiting the scope ofthe embodiments.

Initially, a set of jelly rolls and a pouch to accommodate the jellyrolls are obtained (operation 602). The jelly rolls may be of varyingthicknesses and/or lengths. Next, the jelly rolls are placed within thepouch (operation 604). For example, the jelly rolls may be placedside-by-side, top-to-bottom, and/or stacked within the pouch. The jellyrolls may be glued to the inside of the pouch and/or placed within a setof frames inside the pouch.

For each jelly roll, a first conductive tab is coupled to the cathode ofthe jelly roll (operation 606), and a second conductive tab is coupledto the anode of the jelly roll (operation 608). If additional jellyrolls require coupling to conductive tabs (operation 610), operations606-608 are performed for all remaining jelly rolls in the pouch. Afterall jelly rolls are coupled to conductive tabs, at least one pair ofconductive tabs is extended through seals in the pouch to provideterminals for the battery cell (operation 612). For example, only onepair of conductive tabs may be extended through seals in the pouch ifelectrical connections between the jelly rolls are made within thepouch. On the other hand, multiple pairs of conductive tabs may beextended through seals in the pouch if electrical connections betweenthe jelly rolls are to be made outside the pouch.

Finally, the jelly rolls are sealed in the pouch (operation 614). Forexample, the jelly rolls may be sealed by spot welding and/or applyingheat to the seals. Internal separations between the jelly rolls may alsobe formed during sealing of the jelly rolls in the pouch. As discussedabove, the internal separations may allow voltage increases in thebattery cell if the jelly rolls are connected in series.

The above-described rechargeable battery cell can generally be used inany type of electronic device. For example, FIG. 7 illustrates aportable electronic device 700 which includes a processor 702, a memory704 and a display 708, which are all powered by a battery 706. Portableelectronic device 700 may correspond to a laptop computer, mobile phone,PDA, portable media player, digital camera, and/or other type ofbattery-powered electronic device. Battery 706 may correspond to abattery pack that includes one or more battery cells. Each battery cellincludes a set of jelly rolls connected in series and/or in parallel.

The foregoing descriptions of various embodiments have been presentedonly for purposes of illustration and description. They are not intendedto be exhaustive or to limit the present invention to the formsdisclosed. Accordingly, many modifications and variations will beapparent to practitioners skilled in the art. Additionally, the abovedisclosure is not intended to limit the present invention.

What is claimed is:
 1. A battery cell, comprising: a set of jelly rolls,wherein each of the jelly rolls comprises layers which are woundtogether, including a cathode with an active coating, a separator, andan anode with an active coating; a flexible pouch enclosing the set ofjelly rolls, wherein the jelly rolls are placed side-by-side, placedtop-to-bottom and/or stacked within the pouch so that a cross-section ofthe pouch with the enclosed set of jelly rolls varies in thickness in astepped pattern, including two or more changes in thickness, whereineach change in thickness comprises a step up or step down; a first setof conductive tabs, wherein each tab of the first set of conductive tabsis coupled to the cathode of one of the jelly rolls; and a second set ofconductive tabs, wherein each tab of the second set of conductive tabsis coupled to the anode of one of the jelly rolls, wherein each tab ofthe first set and each tab of the second set of conductive tabs extendsthrough seals in the pouch as external terminals for the battery cell.2. The battery cell of claim 1, wherein the jelly rolls are electricallyconnected within the pouch or outside the pouch using the first andsecond sets of conductive tabs.
 3. The battery cell of claim 2, whereinthe jelly rolls are electrically connected: in a series configuration,in a parallel configuration, or in a series and parallel configuration.4. The battery cell of claim 3, wherein the jelly rolls are internallyseparated within the pouch if the jelly rolls are electrically connectedin the series configuration.
 5. The battery cell of claim 1, wherein thejelly rolls are of different thicknesses.
 6. The battery cell of claim5, wherein the jelly rolls are sealed in the pouch based on anasymmetric battery design.
 7. The battery cell of claim 1, wherein theseals in the pouch comprise at least one of: gluing the jelly rolls tothe inside of the pouch; and placing the jelly rolls within a set offrames inside the pouch.
 8. A portable electronic device, comprising: aset of components powered by a battery pack; and the battery packcomprising one or more battery cells coupled together, wherein each ofthe one or more battery cells includes: a set of jelly rolls, whereineach of the jelly rolls comprises layers which are wound together,including a cathode with an active coating, a separator, and an anodewith an active coating; a flexible pouch enclosing the jelly rolls,wherein the jelly rolls are placed side-by-side, placed top-to-bottomand/or stacked within the pouch so that a cross-section of the pouchwith the enclosed set of jelly rolls varies in thickness in a steppedpattern, including two or more changes in thickness, wherein each changein thickness comprises a step up or step down; a first set of conductivetabs, wherein each tab of the first set of conductive tabs is coupled tothe cathode of one of the jelly rolls; and a second set of conductivetabs, wherein each tab of the second set of conductive tabs is coupledto the anode of one of the jelly rolls, wherein each tab of the firstset and each tab of the second set of conductive tabs extends throughseals in the pouch as external terminals for the battery cell.
 9. Theportable electronic device of claim 8, wherein the seals in the pouchcomprise at least one of: gluing the jelly rolls to the inside of thepouch; and placing the jelly rolls within a set of frames inside thepouch.
 10. The portable electronic device of claim 8, wherein the jellyrolls are electrically connected: in a series configuration, in aparallel configuration, or in a series and parallel configuration. 11.The portable electronic device of claim 8, wherein the battery pack isplaced behind a display of the portable electronic device.